chore: sync CI/CD with upstream guide and update context docs

release.yml: add fallback for existing releases on tag re-push.
installer.nsi: add .onInit file lock check, use LaunchApp function
instead of RUN_PARAMETERS to fix NSIS quoting bug.
build-dist.ps1: copy start-hidden.vbs to dist scripts/.
start-hidden.vbs: embedded Python fallback for installed/dev envs.

Update ci-cd.md with version detection, NSIS best practices, local
build testing, Gitea vs GitHub differences, troubleshooting.
Update frontend.md with full entity type checklist and common pitfalls.

.gitea/workflows/release.yml

@@ -74,9 +74,16 @@ jobs:
               \"prerelease\": $IS_PRE
             }")
 
-          RELEASE_ID=$(echo "$RELEASE" | python3 -c "import sys,json; print(json.load(sys.stdin)['id'])")
+          # Fallback: if release already exists for this tag, fetch it instead
+          RELEASE_ID=$(echo "$RELEASE" | python3 -c "import sys,json; print(json.load(sys.stdin)['id'])" 2>/dev/null)
+          if [ -z "$RELEASE_ID" ]; then
+            echo "::warning::Release already exists for tag $TAG — reusing existing release"
+            RELEASE=$(curl -s "$BASE_URL/releases/tags/$TAG" \
+              -H "Authorization: token $GITEA_TOKEN")
+            RELEASE_ID=$(echo "$RELEASE" | python3 -c "import sys,json; print(json.load(sys.stdin)['id'])")
+          fi
           echo "release_id=$RELEASE_ID" >> "$GITHUB_OUTPUT"
-          echo "Created release ID: $RELEASE_ID"
+          echo "Release ID: $RELEASE_ID"
 
   # ── Windows portable ZIP (cross-built from Linux) ─────────
   build-windows: